I assume this is from "Mr. Pinhole." There's a lot of info at that site, so maybe it tells us somewhere, but my complaint is that there are assumptions behind those calculations and I don't see what criteria he uses. Presumably the coverage is based on some level of exposure fall-off, but it doesn't say what.
Originally Posted by ronlamarsh
In a quick pass i get the (diagonal) field of view of the OP's camera as 117º. That is quite wide, and yes, there will be fall-off. But here's one on paper from my 4x5 with a 103º FOV:
(Scanned and inverted)
Mr. Pinhole seems to think this should be 4.69 inch coverage but what you see is actually over six inches. The camera has a 0.30 mm pinhole at 62 mm from the film/paper.
I've not seen what the OP's pinhole plate actually is. The shot I show here is a hole done by dimple-and-sand in 1 mil brass shim stock -- that's almost a knife edge to begin with. If the hole is made in much thicker stock, the image begins to look like a tunnel view just from the sides of the hole interfering.
Last edited by DWThomas; 05-15-2013 at 08:58 AM. Click to view previous post history.